1. Field of the Invention
The present invention generally relates to an information recording/reproducing system that consists of an information recording apparatus for recording data on an information recording medium, which is exchangeable mainly in a computer system, such as an optical disk (CD-R/RW, DVD-R/RW, DVD+R, DVD+RW), a magneto-optical disk (MO), a magnetic disk (HD, FD, LS120, ZIP), and a memory card (RAM, ROM); an information reproducing apparatus for reproducing the data recorded on the information recording medium by the information recording apparatus; an information recording method for recording the data on the information recording medium; a program for a computer to execute an information recording process; a computer-readable recording medium for storing the program; a host computer; and an information recording/reproducing system for recording the data on the information recording medium according to directions from the host computer.
2. Description of the Related Art
As computers and digital apparatuses become indispensable to businesses and everyday life, there is a growing requirement for information recording media to become versatile, and, among other things, compatibility and perpetuity are often considered important. Especially, magnetic recording media and optical recording media are attracting attention, because they are easy to handle. As the recording density of these media is increasing, and the amount of data to be recorded and reproduced is becoming greater, the capability to handle the data in smaller units than is allowed by conventional methods is required for a finer control of recording and reproduction. However, the recording units and reproducing units are considerably different from apparatus to apparatus, and from medium to medium.
In the case of the CD-R disk, for example, only the disk-at-once (whereby data recording is performed on the entire disk from start to end in one operation) was available as a data recording method in the beginning. Since then, data recording methods based on smaller units have been developed, step by step, namely, data recording units based on units of sessions, tracks, and packets are presently available. In response to these developments, a process for reproducing a desired section of the data has been such that the desired section position is determined by checking the recording units from the largest unit to the smallest unit, one by one. This process clearly slows the reproducing performance, especially in a system with a slow random access capability. In the case of a music CD that is a typical optical information recording medium, the start position and the end position of each music piece are recorded in a certain zone at the inner circumference of the disk for facilitating search for the positions. In this manner, a desired music piece is easily located.
Further, there is another method for facilitating the search, wherein necessary information is embedded in the information recording medium, the embedded information including address information, and information about rotational control; and the information is retrieved when reproduction is to be carried out (for example, refer to JP,2001-52352,A). Further, when searching for a position of desired data in a recordable information recording medium, such as a DVD+R disk, the data position of the desired data is searched for using a larger unit, even though the data position can be determined on a smaller recording unit basis. For example, when searching for fragment information (data position) of target data on the DVD+R disk, access is made to a session disk control block (SDCB) that stores management information for each session until the position of the target data is determined, the SDCB being recorded in the lead-in part of the innermost circumference of the recordable information recording medium.